Carboxylic acid amides

ABSTRACT

The invention concerns new carboxylic acid amides of the formula WHEREIN M denotes a divalent bridge member of the series -S-, S-A-S- and -S-CH2-CH2-(O-CH2-CH2)p-S-, A denotes an alkylene residue containing one to 18 carbon atoms, p denotes an integer from one to three, R1 denotes an alkyl group and R2 denotes alkyl or hydrogen. These compounds are valuable antioxidants for polymers which are damaged by oxidative attacks.

ilited States Biland et al.

let

[151 3,676,49 1 July 11,1972

[54] CARBOXYLIC ACID AMIDES [72] Inventors: Hans Rudolf Biland, Gelterkinden; Max Duennenberger, Frenkendorf, both of Switzerland 73] Assignee: Ciba Limited, Basel, Switzerland [22] Filed: Dec. 4, 1969 [21] Appl. No.: 882,302

[51] Int. Cl ..C07c 103/22 [58] Field of Search ..260/559 T; 252/402 [5 6] References Cited OTHER PUBLICATIONS Takahashi et a], Yakugaku Kenkyu, Vol. 36, 149- 162; (1965).

Primary Examiner-Henry R. Jiles Assistant Examiner-S. D. Winters Attorney-Harry Goldsmith, Joseph G. Kolodny and Mario A. Monaco [5 7] ABSTRACT The invention concerns new carboxylic acid amides of the formula wherein M denotes a divalent bridge member of the series S, -S--A-S and S-CH CH (OCH CH S, A denotes an alkylene residue containing one to 18 carbon atoms, p denotes an integer from one to three, R denotes an alkyl group and R denotes alkyl or hydrogen.

These compounds are valuable antioxidants for polymers which are damaged by oxidative attacks.

4 Claims, No Drawings CARBOXYLIC ACID AMIDES (5) R1 The subject of the invention is the new carboxylic acid H0 OA Ha1 amides of formula R2 R1 R1 HO -NH-C OA- M AC OHN ()H L l wherein M denotes a divalent bridge member of the series with about one mol of a mercaptan of formula 8-, SAS- and SCl-l CH -(O-CH CH S, A denotes an alkylene residue containing 1 to 18 carbon (6) r j atoms, p denotes an integer from one to three, R, denotes an T alkyl group with one to eight carbon atoms and R denotes hydrogen or an alkyl group with one to eight ca b atoms in the form of its alkali salt, with R,, R A and M having the Here the total number of carbon atoms for all A members abovememioned Significance and Hal representing a halogen normally does not amount to more than 36, preferably not atom more than 26 Compounds of formula (2) are for example obtained entire In this formula, the alkylene residues A can be both straight- 20 analogously y reacting about two "1015 of a compound of chain and branched in nature, but in any case represent formula divalent saturated residues. The substituents R, and R can (7 R also be straight-chain or preferably branched in nature. 1

Though both of the positions which are in each case possible for R, and R can be considered, these residues are preferably H0 NH C 0-CH Hal in the o-position to the hydroxyl group. I I I Compounds of formula (1) of predominant practical interest are those which correspond to the formula 1 with about 1 mol of a mercaptan of formula R1 R, Ho-NH-c0c.m.. CnH2nC OHNOH l I l R2 R2 R2 R1 wherein M, denotes a divalent bridge member S, S (8) I 1 (Cl-l S or SCl-l Cl-I --OCH CH -S-, q T T denotes an integer from one to six, n denotes an integer from I one to 12, R, denotes an alkyl group with one to eight carbon m the form of f j i R2 n and moms R2 denotes hydrogen or an alkyl group with one to 40 mg the abovementloned significance and Hal representing a eight carbon atoms and R denotes hydrogen or an alkyl halogen atom group containing one to four carbon atoms. In view of the fact in the case Where 1 Compounds of formula (5) that formula (2) lies within the framework of formula 1), it is are for example condensed Sodlum sulph'de' obvious that R and R cannot simultaneously be different case w i M1 S(CHZ) wherem q has from hydrogen. the indicated significance, compounds of formula (5) are ap- Especially preferred types of Compounds are the of the propriately reacted with the alkali salts of dithiols formula compounds offormula HS(CH ),,SH 9

HO- -NHC 0C Hm-{M11 CnH2n C O-HN --0H wherein M, denotes a divalent bridge member -S or S (CH ),,S, q denotes an integer from 1 to 6, n denotes an in a solvent which is inert towards the reagents (for example 5 5 alcohols or hydrocarbons).

integer from 1 to 12, R, denotes an alkyl group with one to The alkali salts of the dithiols can be manufactured in the eight carbon atoms and R denotes hydrogen or an alkyl group presence of a solvent by using the alkali metal, or through the with one to eight carbon atoms (with the alkyl group for R, use of the stoichiometric amount of an alkali alcoholate. The and R in particular containing one to four carbon atoms), and compounds of formula (5) required as starting substances are furthermore compounds of formula obtained by the reaction, which is in itself known, of acid haa Ra 1-10 NH-o0-cmmm m 0Emu-004m OH wherein M, denotes a divalent bridge member S- or S lides, preferably acid chlorides, of formula (Cl-l S, q denotes an integer from one to six, m denotes an integer from one to four, and R denotes a branched alkyl Hal-A-CO-l-lal 10 group containing one to four carbon atoms. with p-aminophenols of formula The compounds defined above can be manufactured analogously to procedures which are in themselves known. (11) The compounds according to formula l) and analogously, those of the subordinate formulas can appropriately be obtained by reacting about two mols of a compound of formula R2 wherein A, Hal, R and R have the abovementioned significance. This reaction is carried out in the presence of a solvent which is inert towards the reagents, with the corresponding hydrogen halide acid being split off. The resulting hydrogen halide acid can be removed from the reaction mixture by sucking-off, or be bonded by adding a hydrogen halide acceptor, (for example a tertiary amine).

The compounds of formula (1) and of the subordinate fordissolved in ml of methanol are added thereto. The reaction solution is heated for 30 minutes to reflux temperature and is thereafter mixed with activated charcoal, filtered and concentrated to dryness. Yield of crude product: 6.0 g (86.5 percent).

The product for analysis, recrystallized from methylene chloride/cyclohexane, of the compound of formula mulas are suitable for stabilizing oxidation-sensitive organic 13) (CH;) C

materials against oxidation. For this purpose they can be used 10 l in a manner which is in itself known for the following sub- HO NHCOCH2-S strates: homopolymers and copolymers of ethylenically un- J saturated compounds such as vinyl chloride, vinylidene 113): 2 chloride, styrene, butadiene, isoprene, ethylene, propylene, 5

acrylic and methacrylic acid derivatives, for example acrylic acid alkyl esters, acrylamides and acrylonitrile; polyamides, for example from e-caprolactam or from adipic acid and a diamine; polyesters such as polyterephthalic acid glycol ester; natural and synthetic rubbers; lubricating oils; petrol; vegetashows the following data:

Melting point: 228 to 229 C.

Analysis: calculated: C 69.03 H 8.69 N 5.03

found: C 68.87 H 8.65 N 5.00 The compound of formula ble and animal oils and fats; waxes; cellulose and cellulose derivatives such as cellulose esters. 930

The compounds defined above are of preferred importance as stabilizers against oxidative influences in the case of HO NH O O CH2C1 polymerization products of a-olefines, that is to say in the case 2 5 5 of homopolymers and copolymers of a-olefines such as 7 preferably ethylene or propylene, and also in the case of substrates which predominantly contain homopolymersv or copolymers of a-olefines.

For a good antioxidant effect, small amounts of compounds of formula l that is to say about 0.01 to two percent relative to the amount of the substrate to be protected, in general suffice. The antioxidants can for example be incorporated into the materials to be protected directly, that is to say by themselves, or together with other additives such as plasticizers, pigments, light protection agents or optical brighteners, and/or with the aid of solvents.

The antioxidative effect of the compounds of formula (1) also manifests itself in the light exposure test, in that these compounds are able to prevent or greatly to reduce oxidative processes induced by the action of light, for example the yellowing of polyethylene.

The symbols used in the formulas of the present description, such as R,, R m and n, throughout have the same significance which has been precisely circumscribed at least once. In the manufacturing instructions and examples which follow the parts denote parts by weight and the percentages denote percentages by weight unless otherwise stated.

EXAMPLE 1 1.6 g of crystalline 61 percent strength sodium sulphide are dissolved in 100 ml of methanol. 7.425 g of the compound of formula used as the starting material is manufactured as follows: 23.5 g

of 2,6-di-tert. butyl-p-nitrosophenol are dissolved in g of 5 N sodium hydroxide and diluted with 160 ml of water. A solution of 70 g of sodium hydrosulphite in 300 ml of water at about 50 C is added dropwise thereto while stirring. After completion of the addition of the sodium hydrosulphite the mixture is stirred for a further hour. The resulting crystal suspension is filtered off and washed with water until neutral. The moist filter cake of 2,o-di-tert.-butyl-p-aminophenol thus obtained is dissolved in 500 g of methylene chloride and separated from the aqueous phase. The methylene chloride phase is dried over sodium sulphate. After removing the dryv40 ing agent, the mixture is concentrated to 300 g, 45 g of chloracetyl chloride are added dropwise at 20 to 30 C, and the whole stirred for 3 to 5 hours at reflux temperature until no further significant elimination of hydrogen chloride is detectable. The mixture is then finally stirred overnight at room temperature. Thereafter a few solid constituents are filtered off and the reaction solution is concentrated to dryness in vacuo. Yield of crude product: practically quantitative.

The products for analysis, recrystallized from cyclohexane, of formula 12) show the following data: Melting point: 153 to 154 C. Analysis: calculated: C 64.53 H 8.12 N 4.70

found: C 64.38 H 8.17 N 4.77

The compounds quoted below are obtained in an analogous manner (cam 5 HO- -NHC OCH2C1 HONH-C 0A -M AC OHNOH L .l RI! RI]! 1 1!!! 1 2! TABLE 1 Analysis 01'- Meltlng Calculated Found point, B. R" R" A M C. C H N C H N Number:

14 tGI'lLCJHO CH3 H -CH2-- S 247-248 66. 07 7. 68 5. 93 55. 78 8- 00 5. 73 15.... a CH; H CH2 S 214-215 61. 83 6. 23 7. 21 61. 60 6. 30 7. 23 16... tGI't.C4H9 H H CH2 S 217-218 64. 84 7. 26 6. 3O 64. 77 7. 17 6. 42 17.. tert.C4H9 H CH3 CH2- S 270-271 66. 07 7. 68 5. 93 66. 14 7. 87 5. 82 4 B 13811134119 H (CH2)2- S 224-225 69. 82 8. 96 4. 79 69. 57 9. 08 4. 19... tert.C H tert.C H H -(CH2)io- S 163-164 74. 21 10. 46 3. 46 74. 50 10. 44 3. 45

The compounds of formula are obtained from the dried methylene chloride extracts.

The product for analysis, recrystallized from acetone/water, shows the following data: Melting point: 200 to 201 C.

Analysis: calculated: C 66.19 H 8.50 N 4.54 0 AH1 found: C 65.91 H 8.53 N 4.46

| The compounds quoted below are obtained in an analogous Rm manner:

2 11' 11V 110- Nll A M| A- '00 NJ1- --01l L [{I/ Ill! TABLE 3 Analysts of Melting Calculated Found polnt, R R" A M1 C. C II N C II N Number:

27 ten; C 11 CH CH2-- SCHCH2s- 237-238 03.12 7. 57 6.26 63. 04 7. 58 5. 0s :1 CH1 -CH2 SCH2CH2S 202-203 58.90 6. 20 6. 24 58.67 0. 24 0. 21 1s0-C H1 1s0-C3H1 CH2- SCH2CHzS- 182-183 64.25 7. 91 5.00 63. 94 7. 71 4. 86 tort. C111 tort. 0 H; -CH -S(CH2)3S- 194-105 66. 63 8.63 4. 44 66. 39 8.56 4 tort. C 11 tert. C 119 -CH2- S(CH2)4S 218-219 67. 04 8.75 4.34 66.81 0. 01 4.10 tert. 0.1-1, tert. C 110 CH2 -S(CH2)@S 188-190 67. 81 8.90 4.16 67.52 0. 21 3. 03 33 tert. 04H; tert. 0 H, -(CH2)1o- -SCH2CH2S- 58-60 71.84 10. 20 3.22 71.88 10.14 2. 97

The compound of formula a)a X01193 HO -NHOOCHgSCH2OH2OOH2GH2SCH2C O-NHOH 3011011 :1)a

used as the starting material, having the significance given in Table 2 for R, R, R, A and Hal are obtained by reaction of the appropriate acid chloride with the appropriately substituted p-aminophenol.

is manufactured analogously.

Melting point: 174 to 176 C.

Analysis: calculated: C 65.42 H 8.54 N 4.24

found: C 65.64 H 8.72 N 4.21

TABLE 2 Melting point, R R R A C. Hal

Number:

20 tort. 0 11 OH; H OH2- 185-186 Cl 21 CH; CH; H -CH2 163-164 01 22 text. Gil-I H H CH2 107-109 01 23 tert. C4H H CH; CHz 150-151 Cl 24 tort. OJI tert. 04H; H (CIIz)2 171. 5-172 Cl 25.. tert. C 11 cert. 0 11;; II (CH2)1 109-111 Br EXAMPLE 2 EXAMPLE 3 The mercaptide of 1,2-ethanediol is manufactured by introducing 580 mg of sodium into a solution of 1,2-ethanedithiol in 20 ml of absolute alcohol. 7.45 g of the compound of dissolved in ml of absolute ethanol are added to this solution. Thereafter the reaction solution is heated to reflux temperature for one hour and subsequently concentrated to dryness in vacuo, and the residue is taken up in methylene chloride and extracted by shaking with water. 4.0 g of crude 0 TABLE 4 Time until cracks form, in hours at Added Compound C without additive 5 A. Commercially ava ilable antioxidants:

product of the compound of formula 2 i n m |.4 25 (26) (CH3)3C C 3):

11o --NH--()0-CHz--S--CHz--CH -SCHz-C O--N1I OH I I ((']la):(- C (CHO):

Methylene-bis-( 3-methyl-4-hydroxythe degradation of the polymeric material. in a comparison ex- 5-tert. butylbenzene) 28 B. Compounds accord ing to the invention: 5 periment, the melt index of polyethylene samples without ad Formula 3) 850 ditives is determined. Formula (26) 620 Formula (30) 400 TABLE 6 Formula (3 l) 320 10 Melt index Polyethylene, without additive, not aged 3.48 EXAMPLE 4 Polyethylene, without additive, aged 3.81 -Pl thl 'th0.2 art fth com dl3 In parallel experiments, freshly distilled olive oil is oxidized E p o e poun 356 for 20 minutes at 140 C in a pure oxygen stream, both Polyethylene with 0.2 of the compound 26 3 5 (Exampe2) gighout additgves ant; alsto Lilith the addition of, in each case, Polyethylene with 072 pm of 2,6 di ten buty] 4 percent y weig t o t e compounds quoted in Table 5 mflhylphenol below. Thereafter one g of the batch is dissolved tn a mixture Polyethylene with 0.2 part of methylene-bisof ml of carbon tetrachloride, 20 ml of chloroform and 20 Y Y- y l ml of freshly distilled glacial acetic acid. The oxygen dissolved in the form of a gas is expelled by means of a strong stream of 20 nitrogen, after which one ml of saturated potassium iodide We claim: solution is added. The mixture is then well stirred for five 1. Acarboxylic acid amide of the formula HO NHC OA M AC o-zm- -OH L .1

minutes under a nitrogen atmosphere so as to result in a quantitative separation of iodine. After adding 100 ml of freshly distilled water and a little starch solution as the indicator, the mixture is immediately back-titrated with 0.002 N sodium thiosulphate solution until the blue color disappears.

wherein M denotes a divalent bridge member of the series,

SAS- and S-CH -CH (OCH -CH ),,S-, A denotes an alkylene containing one to 18 carbon atoms, p denotes an integer from one to three, R, denotes an alkyl group with one to eight carbon atoms and R denotes Peroxide number milliequivalents of peroxidic oxygen)/kg 3 5 hydrogen or an alkyl group with one to eight carbon atoms.

= ml (sodium thiosulphate solution) 2 2. A carboxylic acid amide according to claim 1, which corresponds to the formula Peroxide number Olive oil, without additive, freshly distilled 0 Olive oil, without additive, oxidized for 20 minutes 334 Olive oil with 0.2 of the compound l3 (partially dissolved) (Example I I28 Olive oil with 0.2 of the compound 26 (Example 2) 78 an integer from one to six, n denotes an integer from one to 12, R, denotes an alkyl group with one to eight carbon atoms, R denotes hydrogen or an alkyl group with l to eight carbon atoms and R denotes hydrogen or an alkyl group containing one to four carbon atoms; R and R cannot simultaneously be different from hydrogen.

3. A carboxylic acid amide according to claim 1 which corresponds to the formula 3 Olive oil with 0.2 of 2,6di-tert.butylwherein M, denotes a divalent bridge member -S(CH 4-methylphenol l22 S, q denotes an integer from one to six, n denotes an integer Olive oil with 0.2 of methylene-bis-(3- methyl-4-hydroxy-S-terLbUtylbenZene 137 from one to 12, R, denotes an alkyl group with one to eight carbon atoms and R denotes hydrogen or an alkyl group with to eight carbon atoms. EXAMPLE 5 4 4. A carboxylic acid amide according to claim 1, which cor- A mixture of 100 g of polyethylene powder (Microthene responds to the formula H0- NIICOC "Hz" Mi C l'iH2n "C OHN -OH I I L J l l R: R2 R1 R2 722, USl) and 0.2 g of one of the compounds mentioned in Table 6 is aged at 85 C for l6 hours in a circulating air oven.

.wherein M, denotes a divalent bridge member -S(CH S, q denotes an integer from one to six, m denotes an integer Thereafter the melt index is determined according to ASTM from one to four and R denotes a branched alkyl group con- Specification D-l238-62-T. The melt index equals the amount of polyethylene, in grams, which has flowed in 10 minutes through a standard die, and represents a measure of taining up to four carbon atoms.

l0l044 moo "53 UNITED STATES PATENT OFFICE QE'HHCTE Q Patent No. 3,676JL9 L Dated July 11, 1972 Inventor(s) HANS RUDOLF BILAND ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, after "Assignee: delete "Ciba Limited" and substitute CIBA-GEIGY AG Signed and sealed this 16th day of April 197A.

(SEAL) Attest: I

EDWARD M..,FLE'ILER,JR C. MARSHALL DANN Attesting Officer Commissioner of Patents CERTIFICATE OF CORRECTION Patent No. 3,676, 1 9 L Dated July 11, 1972 Inventofl s) HANS RUDOLF BILAND ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, after ."Assigneez" delete "Ciba. Limited" and substitute CIBA-GEIGY AG Signed and sealed this 16th day of April 197R.

(SEAL) Attest:

EDWARD NLFLE'I'CHERJH. C. MARSE IALL DANN Attesting Officer commissloner of Patents ha I J 

2. A carboxylic acid amide according to claim 1, which corresponds to the formula wherein M1'' denotes a divalent bridge member -S-(CH2)q-S- or -S-CH2-CH2-O-CH2-CH2-S-, q denotes an integer from one to six, n denotes an integer from one to 12, R1 denotes an alkyl group with one to eight carbon atoms, R2 denotes hydrogen or an alkyl group with 1 to eight carbon atoms and R2'' denotes hydrogen or an alkyl group containing one to four carbon atoms; R2 and R2'' cannot simultaneously be different from hydrogen.
 3. A carboxylic acid amide according to claim 1 which corresponds to the formula wherein M1 denotes a divalent bridge member -S-(CH2)q-S-, q denotes an integer from one to six, n denotes an integer from one to 12, R1 denotes an alkyl group with one to eight carbon atoms and R2 denotes hydrogen or an alkyl group with one to eight carbon atoms.
 4. A carboxylic acid amide according to claim 1, which corresponds to the formula wherein M1 denotes a divalent bridge member -S-(CH2)q-S-, q denotes an integer from one to six, m denotes an integer from one to four and R3 denotes a branched alkyl group containing up to four carbon atoms. 